Suzanne Gordon, chief information officer for software maker SAS Institute Inc., Cary, N.C., "chats" daily via instant message with overseas staffers two or three rungs below her on the organizational chart. During one such session, a manager in France pointed out a flaw in technology support. Canvassing other employees by instant message, Gordon concluded the problem was serious enough for her to appoint a U.S.-based manager to help. "Sometimes through proper channels you don't always get the truth," she says.

Gordon recently "pinged" Philip Busby, a 23-year-old software developer three levels below her, to ask about his iPhone. Busby says he was surprised that Gordon, who oversees 350 employees, knew he had just bought the Apple Inc. device. But "it felt natural to chat with her, it happens all the time," he says. Gordon says she was curious whether the iPhone would be useful at SAS.

Paul Tidball, an SAS product manager who works from his home in Oregon, says instant messaging makes him feel less isolated. Through IM, Tidball finds it easier to collaborate remotely on projects and find co-workers around the clock. He sometimes limits their ability to find him, however, by signing off the instant messenger program. "At some point you just have to put the mouse down," he says.

Connecting people across job categories and time zones can be both the strength and the weakness of the technology. Tim Waire, vice president for information technology in the generation unit of Constellation Energy Group Inc., "tags" colleagues who are not at their computers so he is notified when they start using their computer again. "Because you're a 24-hour company, you expect people to be available 24 hours," he says. "There's no excuse anymore for not being available."

Waire's boss, Beth Perlman, is more cautious. She is Constellation's chief information officer, and she limits her "buddy list" — those who can see whether she is online — to 27 people. But she can still feel overwhelmed. During a recent computer-security investigation, Perlman traded instant messages with two managers while talking to a third on the phone. "The only place I can't be reached is on a plane," Perlman says. "That's why I like flying."

Gordon of SAS agrees. "You cannot let technology control you," she says. "You need to use it to your own advantage."

Consider how Andrew Fano, global director of research at Accenture Technology Labs, seeks control. Fano knows instant messaging is distracting. When he's in charge of a meeting, he sometimes bans laptops. But he also considers it indispensable, and he says that he, too, sometimes uses it during meetings. He has even used it to advise colleagues when to speak up and to suggest points for them to make.